1. Field of the Invention
The present invention relates to a side-emitting LED package for emitting light sideward, and a method of manufacturing the same. More particularly, the invention relates to a side-emitting LED package, which has a reflective layer easily manufactured into desired shapes for emitting light sideward, can be mass-produced in a compact size regardless of an LED chip size, and can have an LED array inside thereof, thereby significantly improving productivity, and a method of manufacturing the same.
2. Description of the Related Art
Recently, an LED package has been increasingly adopted in an LCD backlight unit (LCD BLU). The high power package used for an LCD backlight unit adopts vertical side emission method in which a package with a heat slug mounted thereon is covered by a lens, which results in a problem of a quite large thickness. However, the current trend is that slimmer LCD backlight units require slimmer LED packages therefor.
FIG. 1(a) illustrates a side emitting LED package 200 according to the prior art. In such a conventional structure, a substrate 210 with an LED chip 205 mounted thereon is covered by a lens 212. This entails an additional process of bonding the lens 212 onto the substrate 210 in which a separate lens 212 is manufactured and bonded.
FIG. 1(b) illustrates another conventional LED structure 230. In this conventional technology, a planar reflective film 237 is formed on a molded part 235 on a substrate 232. However, this method is not effective in allowing light from the LED chip 240 to be reflected on the reflective film and reflected sideward from the package.
FIG. 2(a) illustrates further another structure of an LED package 260. This conventional structure is taught in Japanese Patent Publication 10-82916, in which a molded part 262 has a concave depression on an upper surface thereof, and a reflection layer 265 formed on the concave depression to form a light transmitting surface around the sides of the molded part 262. However, in such a conventional structure, the light reflection layer 265 is formed only on some portion of the center of the molded part 262, and an LED chip 270 is mounted on a trapezoid-shaped lead terminal 272.
Therefore, such a conventional structure is limited in emitting light sideward from a conventional upward direction, and the lead terminal results in low productivity per hour.
FIG. 2(b) illustrates yet another LED package 300, which is taught in U.S. Pat. No. 6,674,096 granted to Mathew L. Sommers. In this structure, a transparent molded part 304 wraps around an LED chip 302 and has a reflective surface 306 with a concavely depressed center on an upper surface thereof. And the molded part 304 has a reflective layer 308 formed on the reflecting surface 306, forming a light transmitting surface 310 around the sides of the molded part 304.
In this conventional structure, however, light is scattered upward, and thus is limited in effectively inducing light to be emitted sideward, and also has low productivity per hour owing to the lead terminal.